Ios UIKeyboardWillShowNotification中的条形按钮项目动画

我想不出是怎么回事。我在导航栏上有两个右键，当键盘打开时，我需要A&B键，当键盘关闭时，A和C，或者可能只是C。我这样做了。Im使用UIKeyboardWillShowNotification检查键盘何时打开或关闭

 NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)

 NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)

它很好用。问题是当我调用“KeyboardWillShow”和“KeyboardWillHide”方法时，正确的按钮会飞入。请看这里：

我试过这个，它工作得很好，但只有在不使用键盘的情况下

func dismissKeyboard()
{

    composeTextView.resignFirstResponder()

    self.navigationItem.rightBarButtonItems = nil
    self.navigationItem.setRightBarButtonItem(settingsRightButton, animated: false)

解决方法：

    func textViewShouldBeginEditing(textView: UITextView) -> Bool
{

    self.navigationItem.rightBarButtonItems = nil
    let rightButtons : NSArray = [self.keyboardRightButton, self.cameraRightButton]
    self.navigationItem.setRightBarButtonItems(rightButtons as? [UIBarButtonItem], animated: true)

    return true
}

谢谢

    func textViewShouldBeginEditing(textView: UITextView) -> Bool
{

    self.navigationItem.rightBarButtonItems = nil
    let rightButtons : NSArray = [self.keyboardRightButton, self.cameraRightButton]
    self.navigationItem.setRightBarButtonItems(rightButtons as? [UIBarButtonItem], animated: true)

    return true
}